1. Field of the Invention
The present invention is directed to a new class of azole derivatives of spiroheterocycles. More specifically, the present invention is directed to a new class of azole derivatives of spiroheterocycles useful as fungicides and plant growth regulants.
2. Background of the Prior Art
The control of phytopathogenic fungi is of great economic importance since fungal growth on plants or on parts of plants, i.e., fruits, blossoms, foliage, stems, tubers, roots inhibits production of foliage, fruit or seed and the overall quality of the harvested crop.
Obviously, fungicides are well known in the art. However, the continuous economic toll, discussed above, taken by fungi establish a continuing need to develop new, more effective fungicides which possess curative, preventative and systemic action to protect cultivated plants. Those requirements must be accomplished without any adverse side effects, caused by the fungicide, on the plants to be protected.
Another need in the art is the continual requirement to develop new and effective plant growth regulants. As in the case of fungicides, there is a continuing need in the art to develop new and better plant growth regulants which regulate the growth of plants such that the difficulty and high coast of harvesting economically important plants is significantly reduced. Especially desirable are plant growth regulants that retard undesirable growth, such as excess foliage, of important crops without adversely affecting the yield and quality of the commercial crop to be harvested.
Compounds containing 1,3-dioxolane, 1,3-dithiolane and thiazolidine rings are known in the art. Such compounds are recited to possess spermicida, antimicrobial, anticonvulsant and fungicidal properties depending upon their structure.
Thiazolidine compounds are disclosed in European Patent Application 92,158. The compounds of this disclosure are recited to possess fungicidal properties. The thiazolidine compounds of the '158 application are structurally distinguished from azole derivatives of spiroheterocycles.
U.S. Pat. No. 4,402,963 describes a class of dioxolanylalkyltriazole compounds which are not spiroheterocycles. These compounds are recited to possess important microbicidal properties. They are also set forth to be effective in combating phytopathogenic fungi.
U.S. Pat. No. 4,359,475 is directed to a class of thioketal substituted N-alkyl imidazoles. These compounds, although azole derivatives, are not spiroheterocycles. The compounds of this disclosure are described as possessing utility as spermicides, as antimicrobials and as anticonvulsant agents.
Fundamentally, the compounds disclosed in the above three references are characterized by a following structural formula: ##STR3## Azole derivative of spiroheterocycles have the generic formula as follows: ##STR4##
As the two above formulas establish, spiroheterocyclic compounds are characterized by a linkage between the 2-position bearing the azole moiety and the 2'-position of the aryl ring. The prior art disclosures provide no such linkage as indicated above.
Other references of interest include European Patent Applications 61,789 and 61,794. These two publications disclose the same class of compounds possessing the same utility, antimicrobial properties. The only difference between them is that the former application describes triazole derivatives and the latter application imidazole derivatives. Otherwise, the compounds of these two applications are identical. These compounds are far removed from azole derivatives of spiroheterocycles. It is noted that U.S. Pat. No. 4,483,865 is substantially identical with European Patent Application 61,794.
European Patent Application 29,355 is representative of another class of imidazole or triazole derivatives having utility as microbicidal agents. These azolyl ketals are not only distinguished from the two above-mentioned European patent applications, but are also far removed from spiroheterocycles. The only similarity between the compounds of this European patent application and the compounds of the present invention is that they are said to be effective microbicidal agents, especially in combatting phytopathogenic fungi. U.S. Pat. No. 4,479,004 is substantially identical to European Patent Application 29,355.
Still another class of triazole derivatives, useful as an antimicrobial agent, as a fungicide and as a plant-growth regulant, 1-(beta-aryl)ethyl-1H-1,2,4-triazole ketals, are set forth in U.S. Pat. No. 4,079,062.
Arch. Pharmaz. (Weinheim, Ger.) 308, 94 (1975) discloses certain substituted benzoates, carbamates, and thiocarbamates as well as benzylic ethers prepared as derivatives of 2-imidazolyl-1-indanol and 2-imidazolyl-1-tetralol alcohols and found to be fungicidally active.
Finally, British Patent Application 2,098,607 discloses still another class of triazole or imidazole derivatives useful as agricultural fungicides as well as possessing antimycotic and/or anticonvulsive and anxiolytic agents in the pharmaceutical field. For example, compounds taught in this reference are alleged to provide effective control of parasitic fungi, for treating various forms of epilepsy and psychological diseases. These compounds are far removed from azole derivatives of spiroheterocycles.
The above remarks establish the need in the art for new and improved fungicides and plant-growth regulants. The above discussion, furthermore, emphasizes the uniqueness of azole spiroheterocycle compounds. Such compounds are not only not disclosed in the art, but no teaching of their use as fungicides or plant-growth regulants is made.